You are watching the Indy 500 car race on television with your brother. He says, "Did you know that these cars race at a speed o
f over 200 mph? That velocity is amazing!" Having learned that speed and velocity are not the same, you decide to explain the difference to your brother.
All physical quantities are broadly classified into scalar quantities and vector quantities.
Scalar quantities have magnitude but do not have direction. Vector quantities have both magnitude and direction. Hence the main difference between a scalar quantity and a vector quantity is that a vector has direction while a scalar quantity does not.
Speed is a scalar quantity while velocity is a vector quantity. You have just specified a magnitude of 200 mph without mentioning its direction. This implies that you are referring to speed of the cars in the race and not velocity because velocity of the cars must indicate the direction!
